Pump or motor



M 22, wzm- 4 1,502,310

' W. E. MAGIE ET AL PUMP OR MOT OR Filed Nov. 14. 1923 s Sheets-Sheet 1 INVENTOR. William E. Magze BY nrzd'WaIIer Ferris A TTORNE Y.

July 22 1924. 1,502,310

7 w. E.IMAGIE ET AL PUMP OR MOTOR Filed Nov. 14. 1923 s Sheets-Sheet 2 INVENTOR. William EMagie and Walter Farrzls' Y i I I 1 ATTORNEY. v

July 22 .1924. 1,502,310

w. E. MAGIVE ET AL PUMP OR MOTOR l d N v- 14. 1923 s Sheets-Sheet a I N V EN TOR. Wl'lllkzm E Mag 26 /BY and War/fer frrzl I ATTORNEY.

Patented July 22, 1924.

STATES PATENT OFFICE.

WILLIAM E. MAG-IE, OF BELOIT, AND WALTER FERRIS, OF MILWAUKEE, WISCONSIN,

ASSIGNORS TO THE OILGEAR COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORA- TION OF WISCONSIN.

PUMP on Moron.

Original application filed March 25, I918, Serial No. 224,503. Divided and this application filed November 14, 1923. Serial No. 674,640.

T 0 all whom it may concern.

Be it known that we, WILLIAM E. MAGIE and \VALTER FERRIs, citizens of the United States, residing 'at Beloit, in the county of Rock and State of Wisconsin, and at Milwaukee, in the county of Milwaukee and State of \Visconsin, respectively, have invented a certain new and useful Improvement in Pumps or Motors, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to pumps and fluid motors of the rotary, multiple piston type.

A common use for pumps of this type is in hydraulic transmissions which ordinarily include a motor driven by hydraulic pressure derived from the pump through a closed hydraulic circuit connecting the pump and motor. In some transmissions, the structure of the motor is substantially identical with that of the pump although the type of motor selected is largely dependent upon the demands of the machine to which the transmission is applied.

Hydraulic transmissions for general commercial use require a substantially steady flow pump that will withstand long periods of use at high speeds and under fluid pressures ranging as high as one thousand pounds per square inch or more, without material leakage and without undue wear upon the operating parts. One of the greatest difficulties is that of avoiding wear upon the walls of the several coacting pistons and cylinders of the pum or motor. One com mon cause of this di culty inconstructions heretofore employed lies in the fact that the load carried by each piston and cylinder assembly is ordinarily applied at an angle to the axis of reciprocation of the assembly,

thereby producing a thrust component trans.

verse to such axis which is ordinarily sustained by the coacting piston and cylinder walls.

A primary object of the present invention is the provision of a pump or motor of the type referred to in which the several piston and cylinder assemblies are free from all side thrusts capable of producing any ap preciable wear upon the piston and cylinder walls.

. Other more specific objects and advantages will appear from the following description of an illustrative embodiment of this invention.

This application is a division of our copending application originally filed March 25, 1918, Serial No. 224,503, and renewed August 15, 1921, Serial No. 492,460, the pump and motor hereinafter described being substantially identical with that described in said parent application.

In the drawings:

Figure 1 is a horizontal sectional view of a hydraulic transmission mechanism involving a pump and motor constructed in accordance with the present invention.

Figure 2 is a vertical sectional view of the pump shown in Figure 1.

Figure 3 is a face view of the pump.

Figure 4 is a perspective view of a piston driving element of the pump or motor.

Figure 5 is a similar view of the piston.

Figures 6, 7 and 8 are diagrammatic views illustrating the action of the pump or motor during rotation thereof.

The hydraulic transmission shown includes a casing 10 closed by end heads 11 and 11, respectively. A drive shaft 12 carrying a driving pulley 13 is journaled in bearings 14 in head 11, one end of the driveshaft being keyed in the hub 15 of a pump disk 16 to be hereinafter described. A driven shaft 12 carrying a driven pulley 13 is similarly journaled in bearings 14 in head 11', one end of the driven shaft being keyed in the hub 15 of a motor disk 16. The pump and motor are connected through a closed hydraulic circuit through which power delivered to the pump from the driving pulley 13 is transmitted to the motor and thence through the driven shaft 12 to the driven pulley 13.

The hydraulic circuit in this instance comprises upper and lower pairs of passages 17' and 18 extending through a fixed rail 19 into a pintle20 rigidly supported by the rail and constituting a support for a motor cylinder barrel 21 to be hereinafter described; Passages 17' and 18 are in constant communication with similar passages 17 and 18, respectively, extending through a; block 22 and into a pintle 20 rigidly mounted there-- on and constituting a support for a pump cylinder barrel 21. The rail 19 is fixed in horizontal position within and across the casing 10. The block 22 is mounted for limited sliding movement upon and along the rail, suitable gibs 23 carried bythe block and contacting with inclined faces 24 on the rail serving to maintain the abutting faces of the rail and block in close contact. The position of the block upon the rail is varied and controlled by a screw 25 threaded through the wall of the casing and having a swivel connection 26 with the block.

The structure of the motor shown is substantially identical with that of the pump. Each includes a cylinder barrel 21 or 21 suitably bored as at 27 or 27 and fitted for rotation upon one of the pintles 20 or 20'.

Each cylinder barrel is provided with a series of cylinder bores 28 or 28 radially disposed about the central bore 27 or 27. Each cylinder bore 28 or 28 is provided with a port29 or 29 adapted to register successively with ports 30 and 31 or 30 and 31 formed in the upper and lower surfaces of the pump and motor pintles 20 or 20, respectively. Ports 30 and 30 are in constant communication with the upper pair of passages 17 and 17' in the pump and motor pintles while ports 31 and 31 are always in constant communication with the lower pair of passages 18 and 18, respectively. Thus during rotation of the cylinder barrels of pump and motor, the cylinder bores of the pump, during the upper half of their circular travel, are in communication with those cylinder bores of the motor which are in the upper half of their circular travel, through the ports 2929', ports 30-30, and passages 1717. Similarly, the motor cylinder bores, during the lower half of their circular travel, communicate with hose cylinder bores of the pump whlch are in the lower half of their circular travel, through the ports 2929', ports 31-31', and passages 1818.

A piston 32 or 32 is closely fitted for reciprocation in each cylinder bore 28 or 28'. Each plston carries a crosshead 33 or 33, d sposed opposite and parallel with a reactlon plate 34 or 34 rigidly secured to the inner face of a flange 35 or 35 of the disk 16 or 16' hereinabove mentioned. Between each crosshead 33 or 33 and cooperating reaction plate 34 or 34 is interposed a load transmitting means of such character that all thrusts imposed upon, each crosshead are I applied normal thereto, or, in other words,

parallel with the axis of reciprocation of the corresponding piston and cylinder assembly. In the pump and motor shown, each load transmitting means comprises a pair of rollers 36 or 36 in free rolling contact with and between the opposed faces of each cross-' head and cooperating reaction plate. A positioning cage is associated with each pair formed in the piston.

of rollers. The cage shown comprises a pair of side plates 37 or 37 suitably perforated to journally receive trunnions 38 or 38 on the ends of the rollers. The plates are connected' intermediate their ends by a transverse pin 39 on which a segmental pinion 40 is rotatably mounted. Pinion 40 meshes with appropriate rack teeth 41 formed in the opposed faces of the associated crosshead and reaction plate. The arrangement is such that the rollers 35 or 35 carry and transmit the entire load, the pinion and cage serving to insure proper positioning and rolling action of the rollers during relative reciprocation between each crosshead and reaction face. It will be noted that the spacing .of the rollers is such that they are maintained on opposite sides of the axis of reciprocation of the associated piston during relative reciprocation between the correspondin crosshead and reaction plate.

The isks 16 and 16 are each provided with integral lugs 42 and 42, respectively, disposed beneath and adjacent the crossheads 33 and 33. These lugs come into play to retain the crossheads, rollers 36 and 3G and reaction plates 34 and 34 in properly assembled relation when the pressure of fluid in the cylinders is insufficient for this purpose. These lugs thus serve their purpose When the pump and motor are idle or during the suction stroke of the pump.

In the pump shown, each crosshead 33 is so associated with the piston as to permit a slight rocking action therebetween in a direction normal to the plane of rotation. This action permits each crosshead and piston to accommodate themselves to slight deflec tions in the disk 16 or pintle 20 under load, to thereby avoid any binding action that might otherwise result between the piston and its cooperating cylinder bore. To this end, each crosshead is rigidly connected with a push pin or stem 43 projecting into the hollow piston and provided with a rounded head 44 rockably seated in a socket 45 A pin 46 securely fixed in the crosshead loosely engages suitable perforations 47 in ears 48 carried by the piston so as to loosely retain the piston and crosshead in assembled relation. A circular shoulder 49 snugly fitting within the hollow piston prevents rocking action between piston and crosshead in the plane of rotation, but flats 50 on the shoulder at opposite sides of the stem 43 afford sufficient clearance to permit slight rocking action in a direction substantially normal to the plane of rotation.

In the transmisslon shown, the pump disk 16 and motor disk 16 are provided with integral hubs 15 and 15', respectively, journaled in bearing 51 and 51' in the heads 11 and 11' of the casing so as to rotate about fixed axes m and .22 substantially coincident .and that the cylinder barrel is about its axis y the pressure of fluid within with the axes of the driving and driven shafts 12 and 12. The axis of motor pintle 20', constituting the axis of rotation 3 of the motor cylinder barrel, is permanently offset horizontally from the axis 41:, so that as the disk 16 and cylinder barrel 21 rotate about their respective axes, the pistons reciprocate in their respective cylinder bores and also translate with their crossheads back and forth along their respective reaction plates. By adjusting the block 22 the axis of rotation y of the pump cylinder barrel 21 may be made to coincide with the axis 00 of the pump disk 16 or be disposed horizontally on either side thereof. When these axes are coincident there is no reciprocation of the pump pistons resulting from rotation of the disk and cylinder barrel and pump displacement is zero. When these axes are offset in either direction, the pumppistons reciprocate in their cylinder barrels and translate with their crossheads along their reaction plates, thus delivering fluid to the motor to drive the motor. The rate and direction of flow of fluid delivered by the direction and the y axis from the a:

pump is dependent upon the extent of offset of axis.

A detailed description of the action of the pump will now be given, reference being made to Figures 6, 7 and 8. It will be assumedthat the pump disk 16 is being driven in a clockwise direction about its axis a: rotatable the distance between these axes being E. It will also be assumed that E is one half inch and the fixed distance between the rollers 36 is one and one quarter inches. During rotation the axis of reciprocation of each piston bears a definite fixed relation with respect to axis y, substantially intersecting that axis, but it translates back and forth with respect to the axis an, intersecting this axis in an intermediate position and offset therefrom the distance E in its extreme positions. each crosshead 33 translates correspondingly with respect to its reaction plate 34, and the rollers 36 travel simultaneously one half the distance of travel of the crosshead since they are in rolling contact with the crosshead and reaction plate.

During the pressure stroke of each piston, each cylinder bore 28 produces an outward thrust upon the piston represented by the arrow A substantially coincident with the axis of reciprocation thereof. ,This thrust is sustained by the two rollers, the pressures between the rollers and crosshead being represented by the arrows B and C. Assuming that the thrust A is 1000 pounds and that the crosshead and rollers are in the intermediate position shown in igure 6, then the pressures B and C exerted by the rollers are each 500 .this drag upon each During this translation associated reaction face,

pounds. Then as the crosshead has traveled to the right a distance, say, of one quarter inch to the position indicated in Figure 7, the rollers have each traveled one eighth inch in the same direction. In this position, pressure B is 400 pounds and pressure C is 600 pounds. In the extreme position of these parts shown in Figure 8, the crosshead has traveled its maximum distance E (one half inch) from its intermediate position, and the rollers have traveled one quarter of an inch. In this position pressure. B is 300 pounds and pressure C is 700 pounds. In every position of the crosshead, the pressures B and C exerted by the rollers are inversely proportional to their distances from the line of thrust A, they are parallel to this line of thrust, and their sum is equal to the thrust. The entire pressure or load applied to the crosshead through the rollers may thus be diagrammetrically represented by the resultant thrust L of the roller pressures B and C, which thrust in all positions of the crosshead is equal to and coincident'with the line of thrust A, or, dent with the axis piston.

Rotation of the cylinder barrel 21 is effected from the disk 16 through the piston 32. Such rotation is opposed only by the slight frictional drag between the cylinder barrel 21 and the pintle 20. The effect of piston is to produce a force couple represented by the arrows F tending to tilt the piston and its crosshead. This results in an exceedingly slight decrease in the pressure B exerted by one roller and a corresponding increase in the pressure C exerted by the other roller.

Various changes may be 'made in the embodiment of the invention hereinabove described, without departing from or sacrificing any of the advanta es of the invention as defined in the append ed claims.

7 We claim:

1. In a pump or motor the combination of a pintle, a radial series of piston and cylinder assemblies grouped about said pintle, a reaction member, and separate load transmitting means between said member and each of said assemblies producing a thrust upon the associated assembly substantially coincident with the axis of reciprocation thereof and thereby substantially eliminating side thrusts between the piston and cylinder of each assembly, said means comprising a reaction face on said member extending substantially normal to the axis of reciprocation of each assembly, a crosshead connected with each assembl and reciprocable substantially parallel to the a set of roller elements between each crosshead and face freely movable With respect to and upon said face and crosshead during reciprocation of reciprocation of the in other words, coincithereof, each element of a set producing a thrust on the associated crosshead in a direction parallel to the axis of reciprocation of the associated assembly, a positioning cage for each set of elements freely mox able therewith, and means for controlling the movement of said cage.

2. In a pump or motor the combination of a pintle, a radial series of piston and cylinder assemblies grouped about said pintle, a reaction member, and separate load transmitting means between said member and each of said assemblies producing a thrust upon the associated assembly substantially coincident with the axis of reciprocation thereof, and thereby substantially eliminating side thrusts between the piston and cylinder of each assembly, said means comprising a reaction face on said member extending substantially normal to the axis of reciprocation of each assembly, a crosshead connected with each assembly and reciprocable substantially parallel to the associated reaction face, a set of roller elements between each crosshead and face freely movable with respect to and upon said crosshead and face during reciprocation of said crosshead, said rollers of a set transmitting the load in directions substantially parallel to the axis of reciprocation of the associated assembly and in portions substantially proportionalinversely to their respective distances from said axis of reciprocation, and constraining means for the roller elements of each set for maintaining a roller of each set on opposite sides of said axis of reciprocation.

3. In a pump or motor the combination of a pintle, a radial series of piston and cylinder assemblies grouped about said pintle, a reaction member, and separate load transmitting means between said member and each of said assemblies producing a thrust upon the associated assembly substantially coincident with the axis of reciprocation thereof and thereby substantially eliminating side thrust between the piston and cylinder of each assembly, said means comprising a reaction face on said member extending substantially normal to the axis of reciprocation of each assembly, a crosshead connected with each assembly and reciprocable substantially parallel to the asso ciated reaction face, a set of roller elements between each crosshead and face freely movable with respect to and upon said face and crosshead during reciprocation thereof, and constraining means for each set of elements permitting free movement thereof but maintaining two of said elements on opposite sides of the axis of reciprocation of the associated assembly.

4. In a pump or motor the combination of a pintle, a radial series of piston and cylinder assemblies grouped about said pintle,

a reaction member, and separate load transmitting means between said member and each of said assemblies producing a thrust upon the associated assembly substantially coincident with the axis of reciprocation thereof and thereby substantially eliminating side thrusts between the piston and cylinder of each assembly, said means comprising a reaction face on said member extending substantially normal to the axis of reciprocation of each assembly, a crosshead connected with each assembly and reciprocable substantially parallel to the associated reaction face, and a set of roller elements between each crosshead and face freely movable with respect to and upon said face and crosshead during reciprocation thereof, each set comprising two roller elements maintained on opposite sides of the axis of reciprocation of said associated assembly.

5.111 a pump or motor the combination of a pintle, a radial series of piston and cylinder assemblies grouped about said pintle, a reaction member, and separate load transmitting means between said mem her and each of said assemblies producing a thrust upon the associated assembly sub-' stantially coincident with the axis of reciprocation thereof and thereby substantially eliminating side thrusts between the piston and cylinder of each assembly, said means comprising a reaction face on said member extending substantially normal to the axis of reciprocation of each assembly, a crosshead connected with each assembly and reciprocable substantially parallel to the associated reaction face, and a set of roller elements between each crosshead and face freely movable with respect to and upon said face and crosshead during reciprocation thereof.

6. In a pump or motor the combination of a pintle, a radial series of piston and cylinder assemblies grouped about said pintle, a reaction member, and load transmitting means between said member and said assemblies exerting a thrust upon each assembly substantially coincident with the axis of reciprocation thereof.

7. In a pump or motor the combination of a cylinder barrel having a radial series of cylinder bores, a piston reciprocable in each bore, a reaction member, and load transmitting means between said member and each piston exerting a thrust upon each piston substantially coincident with the axis of reciprocation thereof.

8. In a pump or motor the combination of a cylinder barrel having a radial series of cylinder bores, a piston reciprocable ineach bore, a reaction member, means for effecting an adjustment between said cylinder barrel and member to vary the stroke of said pistons, and load transmitting means between said member and said pistons exertmg a thrust upon each piston substantially coincldent with the axis of reciprocation thereof.

said member to vary the stroke of said pistons, and load transmitting means between said member and said pistons exerting a thrust upon each piston substantially coincident with the axis of reciprocation thereof.

10. In a pump or motor the combination of a member having a radial series of cylinder bores, a piston reciprocable in each bore, a crosshead connected with each piston and extending substantially normal to the axis of reciprocation of said piston, a second member having a series of reaction faces each parallel to and spaced outwardly from one of said crossheads, each crosshead being reciprocable longitudinally of the adjacent face, a set of thrust transmitting elements between each crosshead and face, the rollers of each set being free to move with respect to said face and crosshead during reciprocation of said crosshead and operable to produce thrusts upon said crosshead parallel to the axis of reciprocation of the associated piston, and means for controlling the movement of the rollers of each set so as to maintain a roller of said set at each side of said axis of reciprocation in all working positions of the adjacent crosshead, whereby said rollers react under the thrust to maintain each crosshead and adjacent face in parallelism.

1 1. In a pump or motor the combination of a pintle having fluid passages, a member having a series of reaction faces grouped about said pintle, a piston and cylinder assembly between each face and pintle and subjected to the pressure of fluid in said passages, the axis of reciprocation of each piston and cylinder assembly extending substantially normal to the associated reaction face, a crosshead connected with each piston and cylinder assembly and reciprocable longitudinally of the adjacent reaction face, a set of thrust transmitting roller elements between and in rolling contact with each crosshead and adjacent reaction face through which all thrusts on each crosshead are directed parallel to said axis of reciprocation, a cage associated with each roller set having a differential movement with re- .spect to said crosshead and adjacent face during reciprocation of said crosshead, and

means for restraining the movement of each cage and associated rollers to maintain rollers of the set on opposite sides of said axis of reciprocation whereby said rollers maintain the adjacent crosshead and face in parallelism.

12. In a pump or motor the combination of a pintle having fluid passages, a member having a series of reaction faces grouped about-said pintle, a piston and cylinder assembly between each face and pintle and subjected to the pressure of fluid in said pas sages, a crosshead connected with eachpiston and cylinder assembly and reciprocable longitudinally of the adjacent face, a set of thrust transmitting roller elements between each crosshead and adjacent face, the rollers of each set being free to move along said face and crosshead in rolling contact therewith during reciprocation of said crosshead whereby all thrusts between each crosshead and adjacent face are applied to said crosshead in directions parallel to the axis of reciprocation of the connected piston and cylinder assembly only, and means "for constraining the movement of the rollers of each set to maintain rollers of each set on opposite sides of said axis of reciprocation whereby said rollers of each set react under the thrust to maintain said crosshead parallel with the adjacent face.

13. In a pump or motor the combination of a pintle having fluid passages, a member having a series of reaction faces grouped about said pintle, a piston and cylinder assembly between each face and pintle and subjected to the pressure of fluid in said passages, a crosshead connected with each piston and cylinder assembly and reciprocable longitudinally of the adjacent reaction face, a set of thrust transmitting roller elements between each crosshead and adjacent face, each set comprising two rollers in rolling contact with and movable along said crosshead and face, and constraining means for each roller set permitting such movement but maintaining said two rollers on opposite sides of the axis of reciprocation of the corresponding piston and cylinder assembly.

14. In a pump or motor the combination of a pintle having fluid passages, a member having a series of reaction faces grouped about said pintle, a piston and cylinder assembly between each face and pintle, a crosshead connected with each piston and' cylinder assembly and reciprocable longitudinally of the adjacent reaction face, a set of thrust transmitting roller elements between each face and crosshead within the ends of said crosshead, the elements of each set being free to roll upon said face and crosshead during reciprocaticn thereof, a cage movable with each set of elements, and means associated with said cage for constraining the movement thereof.

15. In a pump or motor the combination of a pintle having fluid passages, a member having a series of reaction faces, grouped der assembly, a cage for each set of elements movable therewith, and means associated with said cage for controlling the movement thereof to thereby maintain said rollers on opposite sides of the axis of the corresponding piston and cylinder assembl l6. In a pump or motor the combination of a member having a centralbore and a series of cylinder bores radiating therefrom, a piston in each cylinder bore reciprocable along the axis thereof, a member having a series of reaction faces one opposite each cylinder bore, a. crosshead connected with each piston and reciprocable relative to an adjacent reaction face, a set of load transmitting roller elements between each crosshead and adjacent face said roller set having a differential movement with respect to and in rolling contact with said crosshead and face, each set comprising roller elements disposed on opposite sides of the axis of the corresponding cylinder bore, a cage for each set of elements movable therewith, and means cooperating with said cage for maintaining said elements on opposite sidesof said axis.

17. In a pump or motor the combination of a cylinder barrel having a central bore and a series of radially disposed cylinder bores in communication with said central bore, a pintle in said central bore having fluid passages for communication with said cylinder bores, a piston in each cylinder bore reciprocable along the axis thereof, a member having a series of reaction faces one opposite each cylinder bore, a crosshead connected with each piston and reciprocable relative to an adjacent reaction face, a pair of load transmitting roller elements between each crosshead and adjacent reaction face, said elements having a differential movement with respect to said face and crosshead during reciprocation of said crosshead, a cage for said elements movable therewith, and means associated with said cage for controlling the movement thereof and thereby maintaining said roller elements on opposite sides of the axis of the corresponding cylinder bore. i

18. In a pump or motor the combination of a cylinder barrel having a central bore passages for communication with said cyl inder bores, a piston in each cylinder bore reciprocable along the axis thereof, a mem-.

ber having a series of reaction faces one op-' posite each cylinder bore, a. crosshead connected with each piston and reciprocable relative to an adjacent reaction face, a pair of load transmitting roller elements between each crosshead and adjacent reaction face, said elements having a differential movement with respect to said face and crosshead during reciprocation of said crosshead, a cage for said elements movable therewith, and a cage centering element intermediate said roller elements and engaging said face and crosshead by which said roller elements are maintained on opposite sides of the axis of the corresponding cylinder bore.

19. In a pump or motor the combination of a cylinder barrel having a central bore and a series of radially disposed cylinder bores in communication with said central bore, a pintle in said central bore having passages for communication with said cylinder bores, a piston in each cylinder bore reciprocable along the axis thereof, a member having a series of reaction faces one opposite each cylinder bore, a crosshead connected with each piston and reciprocable relative to an adjacent reaction face, a pair of load transmitting roller elements between each crosshead and adjacent reaction face, said elements having a differential movement with respect to said face and crosshead during reciprocation of said crosshead,

a cage for said roller elements movable therewith, and a pinion jo-urnaled in said cage between said roller elements and engaging said face and crosshead so as to control said cage and thereby retain said roller In witness whereof, I hereunto subscribe my name this 2nd dayyof November 1923.

WILLIAM E. MAdIE; 

